Effect of three-body interactions on the ordering of bcc binary alloys

The composition dependence of the order—disorder critical temperature is investigated for a model binary alloy equivalent to an Ising system with both the nearest-neighbor interactions (J) and the three-particle interactions (P) present. Using a real-space renormalization-group method for calculating the phase diagram, we find that for small three-body forces, the maximum critical temperature shifts from the 50-50 atomic percent composition …